Racial and ethnic disparities in stroke subtypes: a multiethnic sample of patients with stroke.

Stroke subtypes have been reported to differ by race and ethnic subgroups and have not been adequately explained. We aim to evaluate if the prevalence of vascular risk factors accounts for differences observed in stroke subtypes by race/ethnicity. Patients with acute stroke were prospectively enrolled in the Miami Stroke Registry. Patients' demographic, clinical and radiological characteristics were systematically collected. Stroke subtypes were ascertained using TOAST criteria. The sample was divided into Non-Hispanic Whites (NHW), Hispanics, African Americans (AA), and Non-Hispanic Black Caribbean (NHBC). Univariable and multivariable logistic regression analyses were performed to assess differences among groups. Among 473 stroke patients (mean age 64 ± 14 years; 63.7% were men) of which 52.9% were Hispanic, 22.6% were AA, 13.5% NHBC and 11.0% were NHW. Large artery atherosclerosis was more prevalent in NHBC (OR 1.74, 95% CI 1.02-2.97) than in the other groups. Adjusting for covariates rendered the association not significant (OR 1.71, 95% CI 0.93-3.16). Cardioembolism was more frequent in Hispanics (OR 1.94, 95% CI 1.28-2.96) and NHW (OR 2.66, 95% CI 1.42-4.96) as compared to NHBC and AA combined. Adjusting for covariates, the association was no longer significant for Hispanics but was further strengthened for NHW (OR 3.02, 95% CI 1.42-6.42). Our results suggest that the vascular risk factors prevalence among different racial and ethnic groups partially explains disparities found in the prevalence of some stroke subtypes. Addressing health disparities remains an important public health aspect of stroke prevention.